Growth properties of cultured human endothelial cells on differently coated artifical heart materials

The cultivation of autologous endothelial cells on the blood surface of artificial hearts might prevent their detrimental thromboembolic complications. To investigate the growth characteristics of endothelial cells on theoretically suitable biomaterials, we compared three polyurethanes (Pellethane, Biomer, Enka) and three silicone rubbers (Elastosil, 3145 RTV, Medical Adhesive). All synthetic surfaces were precoated with an extracellular matrix (group 1), fibronectin (group 2), or a glutaraldehyde-preserved cellular matrix (group 3). After the seeding of 2.5 x 104/cm2 human endothelial cells onto the various surfaces, primary adherence, growth kinetics, and maintenance of monolayer integrity were studied for 13 days. On the three polyurethanes all precoating procedures resulted in endothelial cell proliferation and the formation of persistent monolayers. In contrast, on silicone rubbers a persistent coverage with a confluent endothelium could be achieved only on the glutaraldehyde-preserved cellular matrix. When endothelial cell growth was quantitatively assessed on all precoating substrates, the glutaraldehyde-preserved cellular matrix proved to be far superior on each of the synthetics (p < 0.001). These results demonstrate the theoretical feasibility of endothelialization of artificial hearts in vitro. Provided such an endothelium can withstand the mechanical forces within an artificial heart, in vitro endothelialization might contribute to a regained attractiveness of the elective long-term implantation of artificial hearts.